5oik
From Proteopedia
Structure of an RNA polymerase II-DSIF transcription elongation complex
Structural highlights
Function[RPB11_BOVIN] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB11 is part of the core element with the central large cleft (By similarity). [RPB7_BOVIN] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB7 is part of a subcomplex with RPB4 that binds to a pocket formed by RPB1, RPB2 and RPB6 at the base of the clamp element. The RBP4-RPB7 subcomplex seems to lock the clamp via RPB7 in the closed conformation thus preventing double-stranded DNA to enter the active site cleft. The RPB4-RPB7 subcomplex binds single-stranded DNA and RNA. Binds RNA (By similarity). [SPT5H_HUMAN] Component of the DRB sensitivity-inducing factor complex (DSIF complex), which regulates mRNA processing and transcription elongation by RNA polymerase II. DSIF positively regulates mRNA capping by stimulating the mRNA guanylyltransferase activity of RNGTT/CAP1A. DSIF also acts cooperatively with the negative elongation factor complex (NELF complex) to enhance transcriptional pausing at sites proximal to the promoter. Transcriptional pausing may facilitate the assembly of an elongation competent RNA polymerase II complex. DSIF and NELF promote pausing by inhibition of the transcription elongation factor TFIIS/S-II. TFIIS/S-II binds to RNA polymerase II at transcription pause sites and stimulates the weak intrinsic nuclease activity of the enzyme. Cleavage of blocked transcripts by RNA polymerase II promotes the resumption of transcription from the new 3' terminus and may allow repeated attempts at transcription through natural pause sites. DSIF can also positively regulate transcriptional elongation and is required for the efficient activation of transcriptional elongation by the HIV-1 nuclear transcriptional activator, Tat. DSIF acts to suppress transcriptional pausing in transcripts derived from the HIV-1 LTR and blocks premature release of HIV-1 transcripts at terminator sequences.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [SPT4H_HUMAN] component of the drb sensitivity-inducing factor complex (dsif complex), which regulates mrna processing and transcription elongation by rna polymerase ii dsif positively regulates mrna capping by stimulating the mrna guanylyltransferase activity of rngtt/cap1a dsif also acts cooperatively with the negative elongation factor complex (nelf complex) to enhance transcriptional pausing at sites proximal to the promoter transcriptional pausing may facilitate the assembly of an elongation competent rna polymerase ii complex dsif and nelf promote pausing by inhibition of the transcription elongation factor tfiis/s-ii tfiis/s-ii binds to rna polymerase ii at transcription pause sites and stimulates the weak intrinsic nuclease activity of the enzyme cleavage of blocked transcripts by rna polymerase ii promotes the resumption of transcription from the new 3' terminus and may allow repeated attempts at transcription through natural pause sites dsif can also positively regulate transcriptional elongation and is required for the efficient activation of transcriptional elongation by the hiv- 1 nuclear transcriptional activator, tat dsif acts to suppress transcriptional pausing in transcripts derived from the hiv-1 ltr and blocks premature release of hiv-1 transcripts at terminator sequences [RPB3_BOVIN] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB3 is part of the core element with the central large cleft and the clamp element that moves to open and close the cleft (By similarity). [RPB9_BOVIN] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB9 is part of the upper jaw surrounding the central large cleft and thought to grab the incoming DNA template (By similarity). [RPAB4_BOVIN] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Common component of RNA polymerases I, II and III which synthesize ribosomal RNA precursors, mRNA precursors and many functional non-coding RNAs, and a small RNAs, such as 5S rRNA and tRNAs, respectively (By similarity). [RPAB5_BOVIN] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Common component of RNA polymerases I, II and III which synthesize ribosomal RNA precursors, mRNA precursors and many functional non-coding RNAs, and a small RNAs, such as 5S rRNA and tRNAs, respectively. Pol II is the central component of the basal RNA polymerase II transcription machinery. Pols are composed of mobile elements that move relative to each other. In Pol II, POLR2L/RBP10 is part of the core element with the central large cleft (By similarity). [RPAB1_BOVIN] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Common component of RNA polymerases I, II and III which synthesize ribosomal RNA precursors, mRNA precursors and many functional non-coding RNAs, and small RNAs, such as 5S rRNA and tRNAs, respectively. Pol II is the central component of the basal RNA polymerase II transcription machinery. Pols are composed of mobile elements that move relative to each other. In Pol II, POLR2E/RPB5 is part of the lower jaw surrounding the central large cleft and thought to grab the incoming DNA template. Seems to be the major component in this process (By similarity). Publication Abstract from PubMedDuring transcription, RNA polymerase II (Pol II) associates with the conserved elongation factor DSIF. DSIF renders the elongation complex stable and functions during Pol II pausing and RNA processing. We combined cryo-EM and X-ray crystallography to determine the structure of the mammalian Pol II-DSIF elongation complex at a nominal resolution of 3.4 A. Human DSIF has a modular structure with two domains forming a DNA clamp, two domains forming an RNA clamp, and one domain buttressing the RNA clamp. The clamps maintain the transcription bubble, position upstream DNA, and retain the RNA transcript in the exit tunnel. The mobile C-terminal region of DSIF is located near exiting RNA, where it can recruit factors for RNA processing. The structure provides insight into the roles of DSIF during mRNA synthesis. Structure of a transcribing RNA polymerase II-DSIF complex reveals a multidentate DNA-RNA clamp.,Bernecky C, Plitzko JM, Cramer P Nat Struct Mol Biol. 2017 Sep 11. doi: 10.1038/nsmb.3465. PMID:28892040[20] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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